You breed a black, long-haired rabbit with a white, short-haired rabbit. All of the offspring have long, black hair. If the genes for hair color and length are linked, what would be a possible ratio for the F2 population?

If a testcross for two different traits produces more nonrecombinant than recombinant offspring, then the alleles for the two traits

are on the same chromosome.

You are mapping the location of two genes in Drosophila, listless l and blind b. (l+ l+ b+ b+) and (l+ l- b+ b-) flies are normal, but ( l- l- b- b-) flies don't move around very much and cannot detect the location of a light source. You perform a testcross and get the following results: listless, sighted 100 listless, blind 400 normal activity, sighted 400 normal activity, blind 100
What is the distance between these two genes on the chromosome?

They are 20 map units apart.

If a plant species exhibits maternal inheritance for leaf pigmentation, what is the phenotype of the parents of a variegated (green and white leaves) plant?

The maternal plant must be variegated and the paternal plant can be any color.

A man has a mutation in the ATP synthase gene. This results in an inability to synthesize ATP properly, causing extreme muscle weakness. If this man has children, what is the likelihood that they will inherit this disease from him?

0%

A gene for sweat gland production is found on the X chromosome. If a man who lacks sweat glands marries a woman who has normal sweat glands, what will be the phenotype of their children?

All the boys will have sweat glands, and the girls will have sweat glands in some areas but not others.

The Xist gene product

A. is never translated into protein. B. is required for the production of Barr bodies. C. coats the X chromosome with RNA. D. associates with proteins to compact the chromosome. E. All of these statements are correct.

Epigenetic inheritance....

can result in the expression of different alleles in different generations.

Bicoid is a maternal effect gene that is essential for the development of head structures in Drosophila. The F1 generation from a cross of two phenotypically normal flies produces normal embryos, but in the F2 cross, 25% of the embryos lack heads and die. What was the genotype of the mother in the P generation?

Bb

The inheritance pattern where two or more genes do not assort independently because they are close together on the same chromosome is called

linkage.

The inheritance pattern in which the mother provides gene products to the developing egg cells is called

maternal effects.

Albinism in most animals is an epistatic trait characterized by a lack of melanin pigment in the eyes, skin, and hair. If the allele for albinism is a, the allele for brown coat color is B, and the allele for red coat color is b, which of the following genotypes would result in an albino cow?

aaBB and aabb

What are Quantitative traits?

A. are polygenic. B. encode genes for continuous traits. C. are influenced by the environment. D. are both polygenic and influenced by the environment. E. are correctly described by all of these statements.

Height (tallness) in humans is a polygenic trait. Assume the following: There are 4 genes that determine height (Aa, Bb, Cc, Dd). Each dominant allele adds 2 inches of height to an individual. The height of the recessive individual (aa, bb, cc, dd) is 5 feet. What is the height of a person with the genotype (AA, Bb, cc, DD)?

510

In the sweet pea crossing experiment by Bateson and Punnet, the F2 generation had many more offspring with the phenotypes of purple flowers P, long pollen L and red flowers p, round pollen l than expected from independent assortment. This is because

A. in sweet peas, there are always more PL gametes than Pl ones. B. in sweet peas, the alleles for flower color and pollen shape are on the same chromosome. C. there were few recombination events between these genes during meiosis. D. flower color and pollen shape are within the same linkage group. E. All of the statements given are true.

Which of the following statements is not part of Morgan's Theory of Independent Assortment?

Linked genes are always inherited together.

Barr bodies will

be formed in both males and females, depending on the number of X chromosomes possessed by an individual.

Which of the following organelle(s) has/have a genome separate from the genome in the cell nucleus?

In plants, most chloroplasts are inherited from the maternal plant because maternal gametes contribute the most __________ to the zygote.

cytoplasm

The genomes of mammalian mitochondria contain

A. a total of 37 genes. B. genes for proteins used in oxidative phosphorylation. C. genes whose products are used in translation of mRNA. D. ribosomal genes. E. All of the items listed are correct.

Which of the following diseases is not caused by a mutation in a mitochondrial gene?

Turner syndrome

A modification of a gene or chromosome that occurs during gamete formation or early development which permanently alters the expression of that gene for the lifetime of the individual is called

epigenetic inheritance.

If a male cat with orange fur produces female offspring with calico fur, what color was the mother cat?

Black or calico

Which of the following is not evidence supporting the Lyon hypothesis of X inactivation

A genetically normal male cat can never be calico.

ALD is a fatal disease that results from a lack of peroxisomes in the liver. It is diagnosed by the presence of high levels of very long-chain fatty acids in the blood. The disease results in destruction of brain myelin leading to progressive cognitive impairment, coma, and death by the age of 14. There has never been a case of ALD described in girls. You have just started your internship at the Mayo clinic and a 10-year-old girl comes in who is in a coma and having seizures. Blood tests show she has extremely elevated levels of long-chain fatty acids. This looks like ALD, but a girl has never been afflicted. When you go to your supervisor to give your diagnosis, which of the following hypotheses do you present to support it?

Her mother is a carrier, and she could have genetically normal Barr bodies in the liver or Turner syndrome.

The karyotype of a young patient shows two Barr bodies per cell. What condition might this child have?

Triple X syndrome

You discover a gene that results in a complete lack of hair in rats, and you name the gene "chromedome." A cross of homozygous normal and homozygous bald rats results in all bald rats. You conclude that the baldness allele is dominant, but when you repeat the cross with different rats none of the offspring are bald. Extremely puzzled you study your records and discover that in the first cross the bald rat was female, while in the second cross the bald rat was male. What do you conclude from this information?

Chromedome is imprinted in females.

DNA methylation of a gene during spermatogenesis would result in

the inactivation of the paternal allele in the offspring.

Which of the following is NOT a type of epigenetic inheritance?

neither maternal effect nor extranuclear inheritance

Black-cheeked BC zebra finches are extremely desirable, but relatively rare. This phenotype is caused by a recessive mutation, but the mating of two BC birds is considered unethical because it results in very small birds. Therefore, BC birds are created by crossing carriers of the BC gene. Despite problems with the homozygous recessive, some unscrupulous breeders continue to breed them together because of the high prices they fetch. Which of the following statements could explain why BC homozygous birds are unusually small?

The BC gene and growth gene are close together on the same chromosome and/or both of these genes are mutated.

If the recombination frequency between gene A and B is 10 out of 100 offspring, gene A and C is 30 out of 100 offspring, and gene B and C is 40 out of 100 offspring, what is the location of these genes in relation to each other on a chromosome?

either CAB or BAC

What quality of the traits that Mendel chose to study allowed him to establish the basic laws of inheritance?

The alleles that he studied were either dominant or recessive.

A trait that is expressed as a continuum rather than as a few discrete phenotypes is

codominant.

A horticulturist is breeding a new variety of houseplant in which two genes control leaf color. G (allele for green) is dominant to g (yellow) and B (second allele for green) is dominant to b (yellow). The recessive homozygous condition of either gene will mask a dominant allele. What color is a plant with the genotype GgAa?

You are trying to improve growth in an economically important fish species. These fish have a gene for large size with two alleles (L,l). You cross a large female (LL) with a small male (ll) and get all large fish! The genotypes of the F1 are 100% Ll, so you assume that large size is dominant to small. You then cross a small female with a large male and get all small fish! The genotypes of this F1 are normal. How do you explain this result?

The gene for large size is a maternal effect gene.

T or F Maternal effect genes are inherited via the mitochondria.

false

T or F Epistasis often involves genes of an enzymatic Pathway

true

T or F The actions of Xist result in an organism that is a phenotypic mosaic.

true

T or F In biparental inheritance, paternal and maternal gametes provide chloroplasts to the zygote

True

T or FGenomic imprinting can result in offspring with identical genotypes that have different phenotypes.

true

T or FMendel's laws do not adequately explain all the patternss of inheritance.

True

T or FThe DNA methylation state of a zygote will be maintained throughout the life of the organism and then passed on unchanged to its offspring.